NitrOS-9 The best operating system for the Tandy/Radio Shack Color Computer ever.. and it's free!


Mini How-Tos

Access your NitrOS-9 system from a PC
Transfer .DSK images to floppies

Documentation and Tutorials

Getting started with NitrOS-9.

The NitrOS-9 Level 2 Windowing System.

NitrOS-9 Technical Reference.

Shell+ v2.1 Documentation (By Ron Lammardo)

NitrOS-9 Command reference

The NitrOS-9 Level 2 boot process explained

Multivue Manual (From Maltedmedia FTP)

Northern Xposure NitrOS-9 manual (From Maltedmedia FTP)

OS-9 Documentation
(Since NitrOS-9 has many changes over OS-9, this documentation is here mostly for historical reasons.)
OS-9 Level 1 Manual (From Maltedmedia FTP)

OS-9 Level 2 Manual (From Maltedmedia FTP)

OS-9 Level 1 Manual (From Maltedmedia FTP)

OS-9 Level 2 Manuals (Includes Basic09, technical reference, and windowing system) (From RTSI FTP)

NitrOS-9 Frequently Asked Questions

Q. What is NitrOS-9?
A. NitrOS-9 is an "OS-9 compatible" operating system for the TRS-80 Color Computer, Radio Shack Color Computer 2 and Tandy Color Computer 3. It is intended to replace both OS-9 Level One and OS-9 Level Two (once sold by Tandy through Radio Shack stores), as those products are no longer available, and have not been sold for years.

Q. Is NitrOS-9 completely compatible with OS-9 for the Color Computer?
A. Yes, NitrOS-9 maintains compatibility with OS-9 Level One and OS-9 Level Two by using identical system calls and I/O handling. Existing utilities and applications developed for those operating systems should work fine under NitrOS-9.

Q. I thought NitrOS-9 was only for the Tandy Color Computer 3 with a 6309 CPU. Is that true?
A. Historically, NitrOS-9 has been a 6309-only product. However, it has now been ported to the 6809 processor and supports Level 1 for the Color Computer. Since all Color Computers can now run NitrOS-9, the name was extended to cover all Color Computer platforms using either the 6309 or 6809.

Q. How do I know which version of NitrOS-9 is for which Color Computer?
A. NitrOS-9 supports three "levels" and two processors, yielding six potential distributions:

NitrOS-9/6809 Level 1 for the Color Computer
NitrOS-9/6309 Level 1 for the Color Computer with a 6309
NitrOS-9/6809 Level 2 for the Color Computer 3
NitrOS-9/6309 Level 2 for the Color Computer 3 with a 6309
NitrOS-9/6809 Level 3 for the Color Computer 3
NitrOS-9/6309 Level 3 for the Color Computer 3 with a 6309
In short, Level 2 and Level 3 are exclusively for the Color Computer 3. Level 2 is compatible with OS-9 Level Two, and Level 3 contains additional features to manage system memory more efficiently.
Currently, NitrOS-9/6809 Level 1, NitrOS-9/6809 Level 2, and NitrOS-9/6309 Level 2 are available. The other distributions are still under development.

Q. Is it legal to download and use NitrOS-9?
A. NitrOS-9 has been in existence since 1994, having been created by a number of dedicated individuals within the Color Computer community. Much of the code was written by the original NitrOS-9 team: Wes Gale, Bill Noble and Curtis Boyle. Later, Alan DeKok made even further improvements. Therefore, NitrOS-9 is an operating system created by the Color Computer Community, for the Color Computer Community.

Q. How critical is it for me to use NitrOS-9? Can't I just stick with OS-9 Level One or Two?
A. There are two issues with OS-9 Level One or OS-9 Level Two today: first, there is no upgrade path for the products; second, neither operating system has been sold in Radio Shack stores for years, denying new users the ability to purchase valid licenses.
NitrOS-9 is today's and tomorrow's operating system for all Color Computers. It is constantly being improved and enhanced, is freely available, and is also faster and more optimized than Tandy's OS-9 operating systems.

Q. Whatever happened to TuneUp for OS-9 Level Two?
A. That product is now superseded by NitrOS-9.